The mysterious disease behind Christina's World, a painting that became an icon of American art, has finally been determined, experts announced on Friday at the 23nd annual Historical Clinicopathological Conference in Baltimore.

Hanging in the Museum of Modern Art in New York, Andrew Wyeth's artwork depicts the artist's real-life neighbor, Christina Olson. Wyeth was inspired to paint Christina's World after watching her crawl across a field from his window.

It turns out the young woman suffered from an inherited neurological disorder affecting both motor and sensory nerves.

In the painting Christina's legs are bent at an odd angle underneath her body.

"The limbs, particularly the arms, are very thin," Marc Patterson, a professor of neurology, pediatrics and medical genetics at the Mayo Clinic in Rochester, Minn., told Discovery News.

After reviewing Christina Olson's clinical history and studying Wyeth's portrait, Patterson came to the conclusion she suffered from Charcot-Marie-Tooth disease, an inherited disorder caused by mutations that produce defects in neuronal proteins. The disease damages the nerves and affects movement.

Olson presented weakness in her ankles in early childhood. The weakness progressed inexorably - by the time she was 26, she lost the use of her hands and could walk only three or four steps without assistance.

Christina was evaluated at the Boston City Hospital, but tests failed to produce a diagnosis. She was simply told "to just go on living as (she) had always done."

In her late 50s, Christina lost the ability to stand and resorted to crawling to get where she wanted to go.

He noted that some authors suggested that the diagnosis was poliomyelitis, but that disorder has an acute onset, causing mamixum disability immediately, while is essentially stable after the acute period.

"I believe that the best diagnosis for this patient is a form of Charcot-Marie-Tooth disease, specifically a form associated with mitofusin 2 (MFN2) mutations," Patterson concluded.

People with Charcot-Marie-Tooth disease experience weakness in the foot and lower leg muscles. They may have foot deformities such as very arched or very flat feet. Today the disease affects about 1 in 2,500 people in the United States. There's no cure, but some measures can be taken to help patients with their symptoms and increase their mobility.

Patterson found Christina's World a fascinating case. "This painting has long been a favorite of mine, and the question of Christina's ailment was an intriguing medical mystery. I think her case best fits the profile of Charcot-Marie-Tooth disease," he said.

Restorers had wondered what holds together the five wood planks which make up "Visitation," an enigmatic work by the 16th-century Mannerist Jacopo Pontormo. New research suggests they were pieced together with a kind of cheese glue, according to restorer Daniele Rossi.
In fact, cheese glue was often used to join wood planks. The goat or cow cheese-based concoction produced a sticky and thick compound which dried hard as stone, making it extremely hard for wood joints to separate.
Here, Rossi works on restoring "Visitation."

"Visitation" shown before the restoration (left) and after (right).
In addition to finding the super glue, the restorer filled 1,673 woodworm holes and removed the heavy repainting of past restorations. Incisive, luminous colors which previous restorations had covered with a yellow varnish, re-emerged.
The painting depicts in an almost metaphysical way the biblical meeting of the Virgin Mary, pregnant with Jesus, and Elisabeth, pregnant with St. John the Baptist. Staring fixedly into space, two statuesque figures in the background represent their alter egos.